Interlocking wall unit and wall



March 21, 1939. E. A. HORN INTERLOCKING WALL UNIT AND-WALL Filed Dec. 20, 1937 3 Sheets-Sheet 1 March 21, 1939. HORN 2,151,384

INTERLOCKING WALL UNIT AND WALL Filed Dec. 20, 1957 3 Sheets-Sheet 2 l E% I I E /5"" I i i I: i l I 5 i i i I l l I i I I l I I I IIIIIIIII/IIIIIIIIIIIIII[III/IIIIIIIIIIII,IIIIIIIIII'IiII/III March 21, 1939. E. A. HORN INTERLOCKING WALL UNIT AND WALL Filed Dec. 20, 1937 3 Sheets-Sheet S PatentedMar. 21, 1939 PATENT OFFICE 2,151,384 INTEBLOCKING WALL UNIT AND WALL Erwin A. Horn, Seattle, Wash, assignor to I. F. Laucks', Seattle, Wash.

Application December 20, 1937, Serial No. 180,889 21 Claims. (Cl. 20-4) The present invention relates to the art of building construction and more particularly to a novel kind of interlocking wall unit, to the method of using it in construction and to the resulting new type of wall. Reference is made to my previous Patent 1,987,828 which relates to an earlier form of interlocking wall unit of a type however, which requires the use of separate locking means between the individual units to w secure them together. The present invention relates to an improved unit having, among other advantages, the distinctive feature that the locking means is provided in the unit itself so that a series of units which may be made in pairs is, but preferably are duplicates can interlock to form walls which are firmly held together by cooperative action between contacting surfaces.

The principal object of the invention is to providean improved element well adapted for constructing the walls of prefabricated buildings,

particularly dwelling houses and of such character that it can be manufactured in large quantities under low cost factory conditions and then be erected rapidly by unskilled labor. Another object is to provide a unit suitable for panelfaced, double-wall construction with the desirable feature of staggered flush panel joints and with optional provision of dead air chambers to afford insulation, such spaces being suitable for filling, for example, with a dry-fill insulation whenever that type of insulated walls is required.

Another object is to provide a construction wall unit which is self-engaging in such a manner as to provide a wall readily capable of being taken apart and used again in another location where a knocked-down construction is desirable. Another object is to both provide tight abutment of the panel edges and to permit the joint between the panel edges to be formed upon a supporting surface.

To the accomplishment of the foregoing and related ends, the invention, then comprises the features hereinafter fully described and particularly pointed out in the claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however of but a few of the various ways in which the principle of the invention may be applied.

Reference is made to the accompanying drawings in which:

Figure l is an elevation of a typical unit made according to the present invention and of the adjacent portion of another unit.

Figure 2 is a section substantially on line 2-2 of Figure 1.

Figure 3 is a sectional view of a typical interlocking stud or supporting member with attached panel and shows also an adjacent duplicate stud 5 also with attached panel, illustrating one method of providing the studs with interlocking surfaces.

Figure 4 is an elevation showing three units the same as illustrated by Figure I placed in adjacent position ready for interlocking engage- 10 ment.

Figure 5 is a section of the same three units shown in Figure 4 along the line 5-5 and on an enlarged scale, showing the panels and attached stud members in adjacent position ready for in- 5 terlocking engagement but with the horizontal stiffener elements shown in the elevational views omitted.

Figure 6 is a view similar to Figure 5 but showing the parts in final or interlocked relation.

Figure 7 is a vertical section of Figure 4 along the line ll and on the scale of Figure 5, showing the units with the panels and attached horizontal stifiener elements in spaced apart position ready for interlocking engagement.

Figure 8 is the same as Figure 7 except that it shows the parts interlocked, and

Figure 9 is a partial view similar to that of Figure 4 but showing a different lap joint construction and horizontal stiffener element arrangement.

Referring to Figures 1 to 8 of the drawings, throughout which like reference numbers indicate like parts, i indicates the wall panel, to one face of which stud members are attached while the opposite face is exposed on the surface of the wall, 2, 3 and 4 indicate what I shall term normal stud members, 5 illustrates a special tapered stud member which may be designated a wedge stud, used in the preferred form of the inven- 40 tion, and 6 illustrates horizontal interlocking stiffening members which may be used if desired. The unit thus constituted is designated as a whole by the reference character U. Reference numerals la and 5a designate, respectively, the 45 panel and wedge stud of the adjacent panel unit Ua.

The present invention employs panels to form the structural framework of the individual units and also to provide a smooth surface for the resulting wall. The construction is equally well adapted for using any of the forms of panels now available in the building trades. Particularly suitable panels are those made of plywood,

but other forms such as composition panels, insulating board and the like may also be used.

The stud members employed are usually made of wood, but may also be of any suitable material. Cross stiffening members which may be attached to the panel are of the same thickness and made of the same material and conveniently of the same section as the normal stud members. It will be noted by an inspection of Fig. 1 that the stud members 2 to 4 and 5 are of two types, the three normal stud members being .of the same section as shown in Fig. 3, but the wedge stud 5 being of special shape. This latter stud has the same grooved edge as the others but its face is tapered instead of straight.

In the preferred form of the present invention the studs are all provided with one edge grooved or otherwise shaped or molded for interlocking engagement with a similar member. While the form of grooving illustrated in Figure 3 is preferred, any form of grooving capable of interlocking may also be used and in some instances the grooving may be omitted altogether and the stud formed with a straight, plain, vertical edge,

in which case the present invention provides for engagement by friction and wedging-action between the plane surfaces. However, the type of grooving illustrated by Figure 3 is particularly convenient because it is adapted for interlocking engagement with an identical section which has been placed adjacent to it in an inverted position.

As will be described subsequently, the units whose respective facing panels overlap each other in staggered relation in the preferred form of the invention, are respectively inverted and consequently this type of grooving permits interlocking engagement using only one type of molded edge throughout without the complication of using a male grooving on one member and a female form on another as would be necessary if the ordinary tongue and groove shape were selected to provide the interlocking. Other sections than the one shown are also capable of interlocking in inverted position and may be used as well as the tongue and grooved form, which however requires that the proper studs be respectively made with a tongue and the others with a groove so that the units then have to be made in pairs rather than all being duplicates. The preferred form of grooving has the advantage of affording a shape which is readily and cheaply manufactured by the molding or sticker machines available in lumber plants. Thus, except for one special wedge stud member, all the parts of the unit other than the panel may be made from a single shape which can be run cheaply on a sticker machine in large quantities. A desirable shape is a section which can be cut from cheap dimension lumber such as two by fours, two by sixes, and the like, giving a stud about one and one half inches thick, which with quarter inch panels provides a two inch wall. Such dimensions may be varied according to the most economical use of the available materials and the type of wall construction required.

Certain distinctive features of the main component parts having now been described, the construction and operation of the interlocking unit itself will be more readily understood from the following description.

I have discovered that in designing construction units suitable for building panel-faced double-walls there are great advantages in departing from the usual method of attaching the framing members or studs to the panels. In previous practice, for instance as described in my prior patent, No. 1,987,828, the studs are attached in the normal position parallel to the side edges of the panel. I now find that if at least two of the studs are attached in a non-parallel moderately divergent relationship to each other and to the axis of the panel and certain other relationships are maintained, many advantages can be obtained, including frictional attachment of the units to each other and, with suitably grooved stud edges, interlocking frictional attachment.

their ends approach the closest is exactly equal either to the sum of the spaces at the other end of the same or another similar unit panel, separating the inner edges of the studs from the respectively adjacent panel edges. If the divergence is symmetrical as regards the axis of the panel which is parallel to the side edges adjacent to the studs, it will then be found that duplicate units may be assembled to form a continuous double wall of any desired length and the relationships will be the same in all the units, while if the divergence is unsymmetrical, then two sets of right hand and left hand divergent units will have to be made up, and the wall formed with right hand units on one side and left hand units on the other side, but the units will still assemble satisfactorily. It is to be noted that in such assembly in both these instances, the edges which cooperate and come in contact upon assembly, all face towards the middle of the panel.

The cooperative effect obtained by this method is that the two divergent studs on each unit on one side of the wall, engage and clamp together two inverted opposed adjacent units on the opposite side of the wall, in such a manner that the joints between the adjacent panel edges are closed up tightly against each other. To obtain this clamping action with duplicate units the studs must be symmetrically divergent. Obviously, therefore, the spacing between the divergent studs must be at least wide enough to admit two other studs, for upon assembly two other studs have to be interposed between them, each one of the two being attached to another unit. Upon assembly it will be seen that the attachment of the units to each other is a frictional one, due to the wedging action derived from the divergence, and it will be seen that the provision of some form of interlocking shaping of the cooperating stud edges, provides the further opportunity to secure the two sides of the wall to each other by an interlocking action. It will also be seen that staggered flush panel joints are an inherent result .of this construction.

One simple method of designing such a unit is as follows: It is assumed that duplicate rectangular facing panels are provided and that a horizontal line is drawn parallel to and midway between the two panel ends. If two points are selected on that line which are half the length of the line distant from each other and more than the width of two studs away from the nearest panel edge, then any two lines drawn more than the width of two studs apart and more than the width of one stud from the nearest panel edge can form the "pitch plane, or engagement line for frictional engagement between the edges of studs on opposed units. If the lines diverge, the units will engage with a frictional attachment due to wedging action. If the divergence of the lines from each other is unsymmetrical, units which can frictionally interlock will have to be made in sets of right hand and left hand members, but if the lines are symmetrically divergent, then the units can all be made alike forming duplicates. It is, of course, decidedly preferable to have the units all alike although the present invention is not :con-

fined to that arrangement but relates broadly to all arrangements of units capable of forming panel-faced double-wall structures composed of frictionally attached units employing the principle of divergent stud members to obtain the desired frictional attachment of the units to each other by frictional engagement of cooperating stud edges on opposed units.

I find that this principle of divergent stud members can be applied in a variety of ways and combined to good advantage with a number of other features such as:

1. Where only two divergent, like, straight studs are attached to a unit the panel joints are left unsupported. In some instances this defect can be remedied by attaching to each unit a third non-divergent stud parallel to one of the side edges and overlapping it a small amount and duplicate units so designed will fit together with opposed inverted units to form a panel-faced double-wall with staggered joints and with all the panel joints located on and supported by the non-divergent stud.

2. In some cases one of the divergent studs can be located close to one side edge of the panel and if the divergence from the perpendicular is relatively small as is permissible, the stud can be wedge shaped, wider at one end than the other, the non-divergent edge being straight and parallel to the panel edge and overlapping it the desired amount to support the panel joint.

3. The edge of each divergent stud which engages a similar edge on another stud on another unit can, as previously mentioned, be shaped or molded for interlocking engagement. This shape is, of course, preferably one which is adapted for interlocking with a duplicate on another stud which has been inverted. The use of this system provides a very positive interlocking frictional engagement of the respective units and produces a very strong wall.

4. Crosswise and preferably horizontal stiffener members can be attached to the panel running across the spaces between the lengthwise divergent stud members and these members can also be provided with an edge suitable for interlocking engagement with a cooperative member on another unit and if these stifiener members are located with their average plane of engagement with a similar edge or pitch plane spaced symmetrically from the panel ends an additional horizontal interlocking action is provided besides the useful stiffening effect which,

of course, permits relatively thin face-panels to be used.

5. Instead of having only one pair of divergent studs located on each panel, two or more pairs of studs may be used according to the same principle and with the same benefits. In that case, if for example two pairs of studs are used, the cooperating edges of each member of one pair must be mutually parallel and spaced apart the same distance as the similar edges of the other pair, the edges of which are also mutually parallel, but the two pairs may diverge from each other and if certain other relations are correct, the principle of the invention will operate satisfactorily. For many purposes this is the preferred arrangement. It may be combined advantageously with the feature of having one of the edge-studs wedge shaped and overlapping the adjacent panel edge, all of the studs having one edge grooved for interlocking engagement and with similarly grooved stiffening members provided between the studs. When two pairs of studs are used, the divergent pairs of respectively parallel studs may be either separate from each other, one pair placed on the left hand half of the panel and the other on theright hand, or the pairs may be located so that the right hand member of the left hand pair is placed between the members of the other pair on the right hand half of the panel, and correspondingly the left hand member of the right hand pair, placed symmetrically on the left hand half of the panel, but in that case the members of each pair must be mutually parallel and spaced apart the same amount as the other pair as in the first instance.

Attention is now directed to Figure l of the drawings. It is noted that the complete unit U there shown is provided with three normal studs, 2 to 4, and one "wedge stud, 5, that all four studs are provided with one grooved edge suitable for interlocking engagement with a similar edge which has been inverted, that all the studs are attached to the panel by a face and that the single grooved edge on each of the studs is so placed that it faces towards the center of the panel. It is also noticed that the grooved edges of the two studs on the left hand half of the panel form a pair having these grooved edges spaced apart equally so as to be parallel and that the same condition exists on the right hand half of the panel, the spacing-apart of the members of each pair being the same. It is also noticed that the pairs are not placed on the panel in an exactly perpendicular poi; and symmetrically divergent.

It may be mentioned that obviously the method of attaching the stud members to the panels is immaterial. They may be nailed on, or glued, or it would be practical to simultaneously mold both the stud members and panels out of plastic material by injection or similar molding methods so that they all become one piece, the essential feature being the shape and relationship of the parts rather than the material used or method of attachment.

Referring again to the elevation of the preferred form of unit shown in Fig. 1, the method of operation will be more easily understood if the special wedge-shaped stud member, 5. be temporarily disregarded and considered for the moment merely as a duplicate of the other three like stud members, 2 to 4. The four attached studs may then be considered as forming left and right hand. symmetrically divergent pairs, each pair having grooved edges equidistant, mutually parallel, and located so as to face towards the ion but are slightly middle of the panel, each pair comprising an edge stud placed close to one edge of the panel and a middle stud placed near the median line of the panel.

An inspection of Fig. 1 will disclose that, in the preferred embodiment, the distance indicated bythe symbol A is the linear spacing separating the pitch plane of one of the edge studs from the adjacent edge of the panel and the distance B is the corresponding spacing of the opposite edge stud at the same end of the panel. It will be seen that both of these distances, indicated by the symbols A and B, are at the same end of the two edge studs, at the end where the studs come nearest to the adjacent panel edge. The expression pitch plane will be understood as the average meeting plane of two cooperating grooved surfaces when so placed as to interlock. It will then be observed that the distance indicated by the symbol X, at the closest approach of the middle studs at the other end of the panel, indicates the spacing separating the pitch planes of the two middle studs at that point and that the sum of the distances A plus B equals distance X. Correspondingly, since the grooved edges of each member of each pair of studs are parallel, the

spacing between each pair is the same, and the divergence of the pair is symmetrical, the reverse is true, namely, C plus D equals distance Y, where the distance C at the other end of the edge stud from A, is the spacing of the pitch plane at that end of that stud from the adjacent nearest edge of the panel, and the distance D is the corresponding spacing of the opposite edge stud and Y is the spacing of the pitch planes of the middle studs at their point of widest divergence. This relationship C plus D equals Y is then an inevitable consequence of the relationship, A plus B equals X. The slope of the studs or the divergence of the pairs from a perpendicular to the long axis of the panel will be equal to C minus A and the same as D minus B.

Referring now to Fig. 4, which is an elevation of three duplicate units U, Ua and Ub, with the two lower units placed with abutting panel edges and with the third unit, whose parts are distinguished by the letter b superimposed over the junction,

of the two other units, it will be noted that the superimposed unit Ub is inverted end for end and opposed as compared to the two lower units U and Ua. Turning now to Fig. 5 which is a section of Fig. 4 along the line of 5-5, the relative position of the stude and grooved edges of the three units will be observed and it will be seen that the edge studs on the three units are in a position so that when the units are brought together into contact the two edge studs on the inverted upper unit come to rest alongside corresponding middle studs of the two lower units and likewise the two middle studs of the upper unit come down alongside the two adjacent edge studs of the two lower units. If the third unit is then moved into contact upon the two lower units, it will thus fit into place and the studs on the upper unit will come properly into contact with the panel faces on the two lower units.

Turning again to Fig. 4, it will be noted that the upper unit is not placed directly over the horizontal middle line of the two lower ones, but quite a distance above that position. It will now be found possible to slide the third unit downward until it is even with the other two, and during this movement, the adjacent grooved stud edges on the opposed units will all slide into interlocking engagement and come to rest with both adjacent panel edges and the contacting studs tightly wedged together when the panels are even with each other, the final position being indicated by Fig. 6. The minimum movement downward necessary for assembly may be termed the assembly stroke. That the parts will interlock in this position has already been determined by the previously mentioned relationship A plus B equals X. The ends of all the-units are-thus brought into perfectly substantially aligned relation to form the two faces of the double wall.

It is to be noted, however, that the provision of interlocking surfaces on the edges of the studs is not essential since non-interlocking straight edges would engage frictionally with a wedging effect and if'well tightened would offer substantial resistance to separation of the parts and, if before assembly the contacting edges of the studs were supplied with an adhesive, a very strong wall would result upon the setting of the adhesive without requiring the complication of studs provided with an edge adapted for interlocking engagement. Such modification of the present invention is sometimes desirable.

The advantage of the wedge-shaped stud 5, will now be described. If the studs are all four of the same section and properly placed as previously described, and if they are placed symmetrically with the vertical median line of the panel, the effect of interlocking will be as just stated to butt tightly together the adjacent panel edges of contacting units on the same side of the wall. However, under such conditions, the panel joint will be formed without any supporting surface directly behind it; whereas, if one of the edge studs is shaped so that its faces are tapered, the amount of its divergence and the edge that is closest to the panel edge is' thus made straight and parallel therewith instead of divergent like the opposite edge, it is possible to provide support for the junction of the panels by setting all the studs over to one side of'the median line of the panel a small amount so that the straight edge of the wedge stud overlaps the panel edge and the ofiset of the four studs from the median line of the panel is equal to the overlap desired at the edge of the panel. Then, upon assembly of three or more units as indicated by Fig. 4, the junctions of panel edges will come on the overlapping face of a wedge stud and the advantage of a supporting surface for the panel joints will be provided- This is a preferred method of constructing my interlocking unit, but ohviously the interlocking features obtained by maintaining the relationship A plus B equals X can be used independently of this feature.

Attention is now directed towards the stifiening or header members 6 indicated on Fig. 1, and to Figs. 4, 7, and 8 which show also the members 6b. These are preferably members horizontally attached to the units between the studs, but shortened sufficiently to allow clearance for the studs of the other units to pass by their ends during assembly. They may also be attached at a moderate slant if desired. Conveniently, these may be members of the same section as the normal studs, and if the normal studs are provided with grooved edges adapted for interlocking engagement, these stifiener members may also have an interlocking edge and be located with their pitch planes spaced symmetrically distant from the panel ends so that when during assembly a unit is slid downward to interlock two other units, at the moment the stud edges interlock in their final position the stiffening members will also simultaneously interlock. This adds still further to the strength and rigidity of the unit. This relationship is shown by Fig. '7 which is a section of Fig. 4 along the line 1-! showing the stiffening members on respective units in their adjacent positions when ready for assembly, while Fig. 8 shows their position after the unit has been slid downward and interlocking engagement has been attained.

It will be observed that the number and spacing of the stiffening members which can be used without causing the parts to foul each other and make interlocking. assembly impossible is determined by the minimum permissible assembly stroke and the size and dimensions of the unit and its attached parts. In most cases at least three stiffening members can be used. It will be noted that where they are horizontal or substantially horizontal, they provide chambers or pockets which act as dead air spaces within the wall and consequently increase the insulating value of the wall. It will also be apparent to anyone skilled in building construction that various modifications of the length and position of the stiffening-members may be employed so as to facilitate, for instance, filling these pockets with a dry-fill insulating material to further enhance the insulating properties of the wall or add to its fire resistance.

It will be observed that the present construction provides an exceedingly strong and firmly interlocked unit wall construction with the interlocking feature wholly secured by the cooperation of contacting surfaces. It will be apparent also that where a knocked-down construction is desired, walls so constructed can readilybe taken apart. If, on the other hand, permanent construction is the objective,'not only can the contacting interlocking edges be glued, but the tight abutment of adjacent panel edges secured by the features of the present invention furnishes an excellent opportunity for making up the walls with edge glued panel joints, it merely being necessary to provide the edges of adjacent panels with adhesive just before the units are assembled. Where the wedge stud system is employed so that a backing is afforded for the panel joints, a particularly favorable opportunity is provided for forming adhesively united panel joints by my method of forming a groove simultaneouslysin both adjacent panel edges and in a supporting surface and gluing therein a spline member of the same section which after the glue has set can be dressed off smooth with the panel surface to form a flush wall, as disclosed in my United States Patent No. 2,129,497, issued September 6, 1938.

Obviously, it is often desirable to have the panels in walls of this character extend over horizontal plate or sill members, such as are usually required in building construction. This feature is readily obtained with the present invention by extending the panels beyond the ends of the divergent studs an amount at least equal to the thickness of the plates or sills, or equal to whatever amount of overlap is desired. This construction is illustrated in the drawings.

I have found that in constructing ordinary walls, for instance walls having a height of eight feet or more, that the rather considerable length of the studs correspondingly increases the amount ofsliding friction between the stud edges which has to be overcome when the units are being assembled. My practice is to manufacture these unitsunder factory conditions of repetithe units are assembled in their final inverted opposed position, the surface cut away on the stud of one member will be adjacent to a correspondingly cut away surface onthe cooperating member. By the use of this principle greatergor less amounts of contacting surface can be removed so that the frictional resistance to be overcome in assembly can be adjusted to the amount found most desirable for the particular raw materials used and conditions under which the units are manufactured and assembled.

In designing a unit of this character, the necessity of observing certain necessary relationships between the parts will be apparent to any skilled mechanic. For example, the width of the end of the normal studs 2 to 4, plus the width of the narrow end of the wedge stud 5, must be less than the distance indicated-by X, otherwise the non-grooved edges of the edge studs will foul each other at the position indicated by the symbol X and prevent proper assembly. It will also be readily understood that the slope or divergenceof the studs from a perpendicular position, is

due to the fact that the less the slope of the diverging studs the greater will be the holding power of the frictional attachment and also that the narrower the wide end of the wedge stud the less will be the amount of stock required in making it. In selecting the amount of slope best adapted for a particular unit, consideration should also be given to the conveniently allowable minimum stroke of the endwise movement necessary in assembling the units. If the slope of the studs is made too small, an inconveniently long assembly stroke will be required when interlocking edges are used on the studs, in order to allow the respective studs to enter the recess provided for them before they move downward into interlocking engagement. In practice I have found that with the unit approximately eight feet long by four feet wide a slope of two inches is a convenient compromise between these factors when using a stud provided with interlocking edges of the section shown in Fig. 3. It is also desirable when using a wedge stud as a backing for the abutting panel edges, to choose the minimum amount of overlap required for that objective, otherwise it will be seen that the wedge stud becomes unnecessarily wide with consequent waste of stock. It will also be observed that the spacing between the parallel grooved edges of the respective edge studs and middle studs is merely a resulting remainder of space after the slope and the dimensions A and B have been determined. Another point is that the width of the normal studs must not be greater than the distance indicated by the symbol B minus the over lap, if any, otherwise a fouling of the stud ends may occur when they are brought together in space X. Regarding the form of the grooves selected for interlocking assembly, it may be mentioned that obviously the depth of the cooperatinggrooves should not be so great as to unduly restrict assembly by calling for an undue length of assembly stroke such as would be the case where the slope was slight and the depth of groove great. The proportions shown in the accompanying drawings between slope and depth of groove have been found to be satisfactory. Also it may be mentioned that instead of providing the edges with grooves adapted for interlocking with another, similarly grooved inverted surface, an interlocking effect could be obtained by providing an edge that is a straight, true plane, but instead of being vertical to the face of the panel as suggested previously, it could be cut at an angle and arranged so that the face of the stud that is farthest from the attached panel would overhang a certain amount. It is noted that this shape also provides for an interlocking effect when inverted, but I do not consider it advantageous as it has a tendency to wedge the studs oif from their attachment to the panel when the units are interlocked, an effect which is avoided with the shape shown in Fig. 3.

Details such as the foregoing will be readily understood by any skilled workman as soon as the basic principles of the present disclosure have been grasped and hence will not require further description.

In Fig. 9 the wedge stud described in connection with Figs. 1 to 8 is replaced by a fourth normal stud i and a separate batten 8, the latter serving to lap the margin of the adjacent panel. In order to accommodate the batten in the assembled units the cross stiffeners as at 9 may be notched or may consist of spaced parts.

I hereby particularly point out and distinctly claim as my invention:

1. A panel-face double-wall structure having staggered panel joints and composed of mutually attached units, comprising the features that each of said units includes a rectangular facing panel having at least two divergent stud members attached to one side thereof, that the units are assembled with their upper and lower panel ends in substantially aligned relation, that a divergent stud on each of two abutting units on one side of the wall is interposed between two divergent studs on one unit on the opposite side of the wall, and that the adjacent opposed stud edges on the units are mutually parallel and in contact.

2. A panel-faced double-wall structure having staggered panel joints and composed of mutually attached duplicate units, comprising the features that each of said units includes a rectangular facing panel having two stud members attached to one side thereof, that said two stud members are symmetrically divergent from a perpendicular line parallel to the side edges of the panel and midway between the divergent studs, that the spacing between said two divergent studs at their point of closest approach to each other is equal to the'sum of the spaces separating the inner edges of the studs from the respective adjacent panel edges at their point of closest approach to the panel edges, that the units are assembled with their upper and lower panel ends in substantially aligned relation, and that a divergent stud on each of two abutting units on one side of the wall is interposed between two divergent studs on an inverted opposed unit on the opposite side of the wall, and that the adjacent opposed stud edges on the units are mutually parallel and in contact.

3. A panel-faced double-wall structure having staggered panel joints and composed of mutually attached interlocked units, comprising the features that .each of said units includes 2. rectangular facing panel having at least two diver-' gent stud members attached to one side thereof,"

that the centrally facing edges of said divergent studs are shaped for interlocking engagement with a corresponding edge on a similar stud, that the units are assembled with their upper and lower panel ends in substantially aligned relation, that a divergent stud on each of two abutting units on one side of the wall is interposed between two divergent studs on one unit on the opposite side of the wall, and that the adjacent opposed shaped stud edges on the units are mutually parallel and contact in interlocking engagement.

4. A wall structure as set forth in claim 1 including the additional feature that one of the studs attached to each unit has an edge which overlaps a side edge of the facing panel, whereby the joints between abutting panels of the wall are supported by said overlapping stud.

5. A wall structure as set forth in claim 1 including the additional feature that cross panel stiffener elements are provided between the studs, that said stiffener members are provided with an edge shaped for interlocking with a similar edge on another similar member attached to another unit, and that the pitch plane edges of said members are spaced symmetrically with respect to the panel ends whereby the opposed wall units are locked together by the interlocking of the shaped edges of said stiffeners.

6. A panel-faced double-wall structure having staggered panel joints and composed of mutually attached duplicate units, each of said units comprising a rectangular facing panel having left and right hand pairs of studs attached to its rear face, one pair being symmetrically divergent from the other pair, the pairs consisting of an edge stud and a middle stud, the right hand edges of the studs composing the left hand pair being mutually parallel and the left hand edges of the right hand pair being mutually parallel, the pairs being spaced apart the same amount, thesum of the spacing separating the centrally facing edges of the two edge studs at the end of the panel where they approach closest to the panel edge being equal to the spacing separating the closest ends of the mutually adjacent diverging studs, each unit on one side of the wall being attached to two opposed inverted units on the other side of the wall by wedging contact of the edges of the studs on the respective contacting units thrusting the edges of the panels of adjacent units into tight abutment.

7. A construction unit adapted for assembly with two opposed cooperating units to form a panel-faced, double-wall structure having staggered panel joints, comprising a rectangular facing panel having at least two divergent stud members attached to one side thereof, the space between the divergent studs being at least sulficiently wide to admit two interposed similar studs in mutually parallel contacting relation to the centrally facing edges of said divergent studs.

8. A construction unit adapted for assembly with two inverted opposed duplicate units to form a panel-faced double-wall structure having staggered panel joints, said unit comprising a rectangular facing panel having two stud members attached to one side thereof, said two stud members being symmetrically divergent from a perpendicular line parallel to the side edges of the panel and midway between thedivergent studs, the spacing between said two studs being at least sufficiently wide to admit two similar interposed studs.

9. A construction unit adapted for interlocking assembly with two opposed cooperating units to form a panel-faced double-wall structure having staggered panel joints, comprising a rectangular facing panel having at least two divergent stud members attached to one side thereof, the space between the divergent studs being at least sufficiently wide to admit two interposed similar studs in mutually parallel contacting relation to the centrally facing edges of said divergent studs, the centrally facing edges on said divergent studs being grooved for interlocking engagement with a corresponding edge on a similar stud.

10. A construction unit as set forth in claim 6 including the additional feature that one of the studs attached to each unit has an edge which overlaps a side edge of the facing panel, whereby the joints between abutting panels of the wall are supported by said overlapping stud.

11. A construction unit as set forth in claim 6 including the additional feature thatcross panel stiffener elements are provided between the studs, that said stiffener members are provided with an edge shaped for interlocking with a similar edge on another similar member attached to another unit, and that the pitch plane edges of said members are spaced symmetrically with. respect to the panel ends whereby the opposed wall units are locked together by the interlocking of the shaped edges of said stiffeners.

12. A construction unit adapted for assembly with two opposed cooperating units to form a panel-faced, double-wall structure having staggered panel joints, comprising a rectangular fac- "ing panel having left and right hand pairs of studs attached to its rear face, one pair being symmetrically divergent from. the other' pair, the pairs consisting of an edge stud and a middle stud, the right hand edges of thestuds composing the left hand pair being mutually parallel and the left hand edges of the right hand pair being mutually P rallel, the pairs-being spaced apart "the same amount, the sum of the spacing separating the centrally facing edges of the two edge studs at the end of the panel where they approach closest to the panel edge being equal to the spacing separating the closest ends of the mutually adjacent diverging studs.

13. A wall structure comprising inner and outer panels disposed in staggered relation to form inner and outer walls with the joints of each wall substantially upright and lapped by the panels of the other, each panel of one of said walls forming a part of a unit which includes at least a pair of upwardly divergent studs secured thereto, each panel of the other wall forming a part of a unit which includes at least a pair of upwardly convergent studs secured thereto and engaged with adjacent studs of adjacent panels of said one of said walls so that respectively adja cent panels of each of said walls are held together by the lapping panel of the opposite wall.

14. Structure according to claim 13 wherein each panel of each of said walls has a strip secured to one lateral margin and projecting therebeyond to lap the adjacent panel margin.

15. structure according to claim 13 wherein each panel of each of said walls has a strip secured to one lateral margin and projecting therebeyond to lap the adjacent panel margin, and wherein said strip is constituted by a part of one of the studs.

16. Structure according to claim 1 wherein the units whose panels constitute the inner and outer walls are duplicates.

17. A wall unit comprising a panel and a pair of studs secured to a face of said panel, said studs being upwardly extending when the panel is upright and having adjacent faces divergent in opposite directions from the vertical.

18. A wall unit according to claim 17 wherein the stud faces are symmetrically divergent.

19. A wall unit according to claim 17 wherein a projecting batten is secured to one lateral margin of the panel face. Y

20. A wall unit according to claim 17 wherein a second pair of studs is secured to the panel face outwardly of the first and have adjacent faces divergent as the divergent faces of the first pair.

21. A wall unit comprising a-panel and a pair of studs secured to a face of said panel, said studs being upwardly extending when the panel is upright and having adjacent longitudinally diver- 

